There are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

There was an earlier war when George Washington was *not* shot. Was there a Founding Father eho could have had a presidency that set the same pattern for the new nation? Not least, not having a dynasty to ensure, so stepping down after a while in favor of... of whoever was chosen to replace him. Still, if we didn't have him, I don't know how far the time travellers would cast their net for him, if they would've found a "good enough" selection elsrwhen.

Post by Jack BohnThere was an earlier war when George Washington was *not* shot. Wasthere a Founding Father who could have had a presidency that set thesame pattern for the new nation? Not least, not having a dynasty toensure, so stepping down after a while in favor of... of whoever waschosen to replace him. Still, if we didn't have him, I don't know howfar the time travellers would cast their net for him, if they would'vefound a "good enough" selection elsrwhen.

Reminiscent of "If Lee Had Not Won at Gettysburg," by none otherthan Winston Churchill.

However, if you're postulating a universe in which Washingtonfounded a dynasty, I have to point out that geneticists haveconcluded (from his appearance, something about the eyelids)that he was an XXY male and as sterile as boiling water. MarthaWashington had had several children by her first husband, Mr.Custis, none by George.

There was an earlier war when George Washington was *not* shot. Was there a Founding Father who could have had a presidency that set the same pattern for the new nation? Not least, not having a dynasty to ensure, so stepping down after a while in favor of... of whoever was chosen to replace him. Still, if we didn't have him, I don't know how far the time travellers would cast their net for him, if they would've found a "good enough" selection elsrwhen.

Reminiscent of "If Lee Had Not Won at Gettysburg," by none other than Winston Churchill.

However, if you're postulating a universe in which Washington founded a dynasty, I have to point out that geneticists have concluded (from his appearance, something about the eyelids) that he was an XXY male and as sterile as boiling water.

However, if you're postulating a universe in which Washington founded a dynasty, I have to point out that geneticists have concluded (from his appearance, something about the eyelids) that he was an XXY male and as sterile as boiling water.

No, I'm suggesting a dynasty from the general the Continental Army had to get instead, or the guy who defeated him for President. Could time travellers fleeing the Imperial States of America be merely looking for sterility? No, I can only picture we had George and wanted him back after some Spider and Snake back-n-forthing. (Although keeping a guy from getting shot on a battlefield takes some doing.)

Post by Dorothy J HeydtHowever, if you're postulating a universe in which Washingtonfounded a dynasty, I have to point out that geneticists haveconcluded (from his appearance, something about the eyelids)that he was an XXY male and as sterile as boiling water. MarthaWashington had had several children by her first husband, Mr.Custis, none by George.

XXY or Klinefelter's syndrome is one of many possible causes ofWashington's infertility that have been discussed over the years.Here is what John K. Amory wrote about it in 2004:

"Klinefelter's syndrome is typified by tall stature, testicularfailure, and mild to severe cognitive deficits, especially in termsof visualospatial and language abilities. Klinefelter's syndromecould explain Washington's remarkable height. Washington wasextremely tall — probably more than 6 feet 3 inches — a veritablegiant for his age; however, tall stature was a family trait. Adiagnosis of Klinefelter's syndrome would also provide an explanationfor his well-documented dental woes, because many individuals withKlinefelter's syndrome suffer from taurodontism, a geneticenlargement of the tooth pulp, which predisposes to premature dentalcaries.

Arguing against Klinefelter's syndrome are contemporary descriptionsof Washington as powerfully muscled and as a superb horseman,certainly not consistent with hypogonadism and visuospatialdysfunction. In addition, Washington's speeches and survivingwritings demonstrate a superior facility with language, makingKlinefelter's syndrome seem very unlikely.(https://www.fertstert.org/article/S0015-0282(03)03058-9/fulltext)

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

The guy who suggested John Frederick Parker, the policeman who wasguarding the door to Lincoln's box at Ford's theatre, go drinking withLincoln's footman and coachman, instead of staying at his post.

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

Franz Ferdinand's driver drove past the exact spot where Gavrilo Princip was and then STOPPED! Clearly the driver was a time agent intent on starting WW1.

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

I have often wondered about Tsuda Sanzō, the policeman who tried toassassinate the Russian crown prince (the future Nicholas II) whenthe latter visited Japan in 1891.

To the best of my knowledge, Tsuda had had a clean record during hismilitary career and had no reason to attack Nicholas whom he wassupposed to be protecting. The reasons that he gave during his trial-- that the crown prince's visit was a Russian plot against Japanetc -- were bizarre.

On the other hand, if Tsuda was a time traveler from the future, itmay make sense. The assassination attempt was botched even thoughTsuda was very well trained and experienced: Nicholas was wounded,but the wound was not life-threatening. Still, he cut his visit shortand left the country. Years later, when he was emperor and Russia'srelationship with Japan deteriorated, Nicholas's opinion of Japan wasan important factor during the maneuvering that preceded theRusso-Japanese war. If Tsuda's plan was to make a future war morelikely and put the whole sequence of events that ultimately led tothe Communist takeover in 1917 into motion, it may have been a greatsuccess. Kind of makes you wonder what kind of future he was tryingto prevent...

Post by AhasuerusIf Tsuda's plan was to make a future war morelikely and put the whole sequence of events that ultimately led tothe Communist takeover in 1917 into motion,

... and what followed.

Post by Ahasuerusit may have been a greatsuccess. Kind of makes you wonder what kind of future he was tryingto prevent...

Possibly the future where we didn't see the Dinosaur Killer of2053 in time to nudge it away from Earth?Apart from that, it is hard to imagine (from today's perspective)that a future time traveller would not try to stop the World Warsand the atrocities of the Big Three.

And potentially make things worse? I think a future time travellerwould be quite careful to not perturb the timeline; unless the multiversetheory holds, in which case the time traveller would simply branch anew timeline (while the original continues along its inevitable trajectory..).

Post by AhasuerusIf Tsuda's plan was to make a future war morelikely and put the whole sequence of events that ultimately led tothe Communist takeover in 1917 into motion,

... and what followed.

Post by Ahasuerusit may have been a greatsuccess. Kind of makes you wonder what kind of future he was tryingto prevent...

Possibly the future where we didn't see the Dinosaur Killer of2053 in time to nudge it away from Earth?Apart from that, it is hard to imagine (from today's perspective)that a future time traveller would not try to stop the World Warsand the atrocities of the Big Three.

It's hard to tell without knowing what the alternatives were. PerhapsTsuda was thinking "I can't imagine anything that could be worse thanwhat actually happened during *our* 20th century!"

Another thought: what if Tsuda messed up (easy to do if you are in anunfamiliar body)? What if the plan was to get rid of Nicholas, anotoriously under-qualified emperor, and hope that his replacementwould be more competent?

Post by AhasuerusIf Tsuda's plan was to make a future war morelikely and put the whole sequence of events that ultimately led tothe Communist takeover in 1917 into motion,

... and what followed.

Post by Ahasuerusit may have been a greatsuccess. Kind of makes you wonder what kind of future he was tryingto prevent...

Possibly the future where we didn't see the Dinosaur Killer of2053 in time to nudge it away from Earth?Apart from that, it is hard to imagine (from today's perspective)that a future time traveller would not try to stop the World Warsand the atrocities of the Big Three.

Because without the rapid advancements in technology spurred by theworld wars time travel wouldn't have been invented!

https://www.tor.com/2011/08/31/wikihistory/

--Inquiring minds want to know while minds with a self-preservationinstinct are running screaming.

Post by Dimensional TravelerBecause without the rapid advancements in technology spurred by theworld wars time travel wouldn't have been invented!

Time travel won't be invented.

When it's been invented on various timelines, some idiots keepgoing back in time and changing the past. They keep doing thisuntil they've produced a timeline in which time travel is neverinvented. Therefore, the only timeline that remains intact isthe one in which time travel is never invented.

Post by Dimensional TravelerBecause without the rapid advancements in technology spurred by theworld wars time travel wouldn't have been invented!

Time travel won't be invented.

Because there is no such thing as time nor motion. Like a film, life isa series of still pictures, not a video that can be rewound and edited.(Props to Selby referenced in Frann O'Brien's The Third Policeman.)

Post by Mike Van PeltWhen it's been invented on various timelines, some idiots keepgoing back in time and changing the past. They keep doing thisuntil they've produced a timeline in which time travel is neverinvented. Therefore, the only timeline that remains intact isthe one in which time travel is never invented.

It might appear to be so from our joint experience but if our creator isgetting things wrong, this world may have just been created with fakehistory such as dinosaur bones gnawed on by human teeth. And tomorrowthere may be a new version.

I think he made it up. How many idiots? In reality, some more idiotswould keep going back and changing the past until they produced atimeline in which the original group of idiots were never created.That is why there are all these free electrical outlets appearing incarparks when the real purpose is to provide emergency charging forsmaller-batteried personal time machines from the 3570s when everyonehas one, even the Burmese Loonies, the North Korean Martians, the IraqiJupes and Palestinian Saturninians. Jeez. Even the Russian Assholes musthave them as well.

Because there is no such thing as time nor motion. Like a film, life isa series of still pictures, not a video that can be rewound and edited.(Props to Selby referenced in Frann O'Brien's The Third Policeman.)

On thinking about this, I realized... that while that _seems_ tobe a possible reason for no time travel, it actually gets itbackwards.

It's precisely _because_ time and motion exist that the idea ofgoing back in time is impossible; to travel to the past, one hasto change time into space so that one can, in a certain amountof time, move from the place called "now" to the placecorresponding to the past moment you wish to visit.

Of course, that may just explain how a time machine would haveto work rather than making it impossible.

Essentially, the notion of time travel assumes that thedirection of time is just like the other directions of space(relativity, which does make it a direction, still makes itspecial by involving the square root of minus one)...

and so the time traveller has to take his personal direction ofsubjective time, and have it now cease to point down the timeaxis of our fourth-dimensional universe, but instead have itpoint in a fifth direction, perpendicular to all the others.

But in that case, his subjective passage of time ought to carryhim away from our four-dimensional universe, rather thanallowing him to get into the past. Of course, if he can turn 180degrees in that fifth dimension halfway through his journey, itwould work out... and then he points himself forwards in timeagain to fit in.

My point is that time travel is impossible whether time is likespace, or it is like time. Time travel requires it to bepossible to have time be both like time and like space,whichever one you choose during part of your journey.

Post by QuadiblocIt's precisely _because_ time and motion exist that the idea ofgoing back in time is impossible; to travel to the past, one hasto change time into space so that one can, in a certain amountof time, move from the place called "now" to the placecorresponding to the past moment you wish to visit.

Dude, the latter is EASY. You do it every time you slow down.

No, the impossible part is getting a motion vector that WAS pointing into thefuture lighg-cone to point into the past light-cone instead. Even WITH ftl itcan't be done, the transforms smack up against the light-cone walls. Andwithout ftl, you can't even get out of the future light-cone.

Post by QuadiblocEssentially, the notion of time travel assumes that thedirection of time is just like the other directions of space(relativity, which does make it a direction, still makes itspecial by involving the square root of minus one)...

It's manifestly not the same; its metric sign is the negative of space's.You can rotate spatial dirctions into each other with ordinary rotationmatrices, using regular trig functions; to inter-rotate time and space,you need the full Lorentz transform, using hyperbolic trig functions.

(We have only one time axis, so the only possible "rotation" of time axesinto each other would be reflecting it, which isn't continuous at all.)

Post by QuadiblocBut in that case, his subjective passage of time ought to carryhim away from our four-dimensional universe, rather thanallowing him to get into the past. Of course, if he can turn 180degrees in that fifth dimension halfway through his journey, itwould work out... and then he points himself forwards in timeagain to fit in.

ObSF (no really): Greg Egan, _The Clockwork Rocket_/_The Eternal Flame_. Lifeand space exploration and existential dangers in a setting where relativitydecidedly does NOT work the same way as ours.

Post by QuadiblocMy point is that time travel is impossible whether time is likespace, or it is like time. Time travel requires it to bepossible to have time be both like time and like space,whichever one you choose during part of your journey.

... but time IS like both time and space. It's just always pointed along time,is all.

Dave, really, you ought to know by now that trying to do philosophy aboutspacetime fails utterly unless you show the math involved

--\/David DeLaney posting thru EarthLink - "It's not the pot that grows the flowerIt's not the clock that slows the hour The definition's plain for anyone to seeLove is all it takes to make a family" - R&P. VISUALIZE HAPPYNET VRbeable<BLINK>my gatekeeper archives are no longer accessible :( / I WUV you in all CAPS! --K.

Post by QuadiblocIt's precisely _because_ time and motion exist that the idea ofgoing back in time is impossible; to travel to the past, one hasto change time into space so that one can, in a certain amountof time, move from the place called "now" to the placecorresponding to the past moment you wish to visit.

Dude, the latter is EASY. You do it every time you slow down.

I wasn't talking about relativity here. Special Relativity, of course, in itsown way, suggests that time travel is not possible - or assumes that time travelis not possible, and concludes from that that faster-than-light travel isimpossible as well.

Instead, I was looking at this from a purely classical point of view.

This is because I was responding to a post that said that time travel wasimpossible... because time and motion are illusions, all history is staticwithin a four-dimensional object.

The trouble is, life and consciousness would also be impossible if that were thecase. If those are real, time and motion must be real.

And if time and motion are real, then the direction in which time and motiontakes place is utterly unlike the directions of space. And "time travel" ispremised on them all being the same - if one has the right key.

Now, relativity does mix them up... sort of... but that square root of minus onethingy keeps them from getting mixed up in ways that cause problems. Thedifference between the two still exists, it's just subtler and more complicated.

Post by QuadiblocThe trouble is, life and consciousness would also be impossible if that werethe case. If those are real, time and motion must be real.

... okay, so why are you assuming life and consciousness are real? Eithertogether or separately?

Dave, we can demonstrate that you have no life, and we have severe doubtsabout your state of consciousness, so you can't use yourself as an example.And I'd like to see you try to prove _I'm_ not a hallucination you're having

--\/David DeLaney posting thru EarthLink - "It's not the pot that grows the flowerIt's not the clock that slows the hour The definition's plain for anyone to seeLove is all it takes to make a family" - R&P. VISUALIZE HAPPYNET VRbeable<BLINK>my gatekeeper archives are no longer accessible :( / I WUV you in all CAPS! --K.

Post by QuadiblocIt's precisely _because_ time and motion exist that the idea ofgoing back in time is impossible; to travel to the past, one hasto change time into space so that one can, in a certain amountof time, move from the place called "now" to the placecorresponding to the past moment you wish to visit.

Dude, the latter is EASY. You do it every time you slow down.

I wasn't talking about relativity here. Special Relativity, of course, in itsown way, suggests that time travel is not possible - or assumes that time travelis not possible, and concludes from that that faster-than-light travel isimpossible as well.

You're incapable of learning, aren't you.

I will quote Kip Thorne on this matter: "The laws of generalrelativity by themselves do not enforce chronology protection: it iseasy to find solutions of the Einstein field equations that haveclosed timelike curves." Considering that (a) Kip Thorne has a NobelPrize in physics and (b) Kip Thorne was one of the authors of"Gravitation", which was for a long time the standard text on GeneralRelavity, and that (c) you don't have either, I believe that we aresafer in accepting Kip Thorne's view on this matter than we are inaccepting yours. Perhaps you should accept that as well and move oninstead of trotting out Special Relativity once again every time thetopic comes up.

<http://inspirehep.net/record/366943/files/pdf.pdf>. 21 pages onrelativistic time travel starts on page 295. This is a physics paperintended for physicists, delivered by the recognized expert on thetopic.

Note that he, the world's expert on such matters, does not evenattempt to cite special relativity as a reason that time travel wouldbe impossible. If it were that easy then he would have just done itand gone home.

Post by QuadiblocInstead, I was looking at this from a purely classical point of view.

Which is meaningless when there is established physics that actuallyhas something relevant to say on the topic.

Post by QuadiblocThis is because I was responding to a post that said that time travel wasimpossible... because time and motion are illusions, all history is staticwithin a four-dimensional object.

So why did you not appeal to General Relativity which has a great dealto say about dynamics in four dimensions?

Post by QuadiblocThe trouble is, life and consciousness would also be impossible if that were thecase. If those are real, time and motion must be real.And if time and motion are real, then the direction in which time and motiontakes place is utterly unlike the directions of space. And "time travel" ispremised on them all being the same - if one has the right key.Now, relativity does mix them up... sort of... but that square root of minus onethingy keeps them from getting mixed up in ways that cause problems. Thedifference between the two still exists, it's just subtler and more complicated.John Savard

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

I have often wondered about Tsuda Sanzō, the policeman who tried toassassinate the Russian crown prince (the future Nicholas II) whenthe latter visited Japan in 1891.To the best of my knowledge, Tsuda had had a clean record during hismilitary career and had no reason to attack Nicholas whom he wassupposed to be protecting. The reasons that he gave during his trial-- that the crown prince's visit was a Russian plot against Japanetc -- were bizarre.On the other hand, if Tsuda was a time traveler from the future, itmay make sense. The assassination attempt was botched even thoughTsuda was very well trained and experienced: Nicholas was wounded,but the wound was not life-threatening. Still, he cut his visit shortand left the country. Years later, when he was emperor and Russia'srelationship with Japan deteriorated, Nicholas's opinion of Japan wasan important factor during the maneuvering that preceded theRusso-Japanese war. If Tsuda's plan was to make a future war morelikely and put the whole sequence of events that ultimately led tothe Communist takeover in 1917 into motion, it may have been a greatsuccess. Kind of makes you wonder what kind of future he was tryingto prevent...

Boy King Tutankhamun reigned from the age of 9 until he died at the ageof 19. His grandfather-in-law Ay advised Tut and later became Pharaohfor a few years after Tut passed.Tut and Ay together restored Amun monotheism to prominence, whichdiminished the secular Aten quasi-monotheism that Tut's fatherintroduced. After Ay passed, Horemheb, the commander-in-chief of thearmy, usurped the throne. Horemheb removed Amun monotheism and restoredsecular Aten quasi-monotheism. Horemheb also instigated a campaign tosend Tut, Ay, and their ideas down the old Orwellian memory hole beforeit had a name.King Tut walked with a cane due to leg injuries that included acongenital clubfoot. He also contracted multiple malaria infections fromseveral strains of the oldest known parasites. His malaria aggravatedhis poor health and kept his left leg from properly healing, whichcontributed to his death.It's plausible that a traveler took modern malarial parasites backin time to quietly assassinate Tut under non-suspicious circumstances.This in turn prevented the rise of Egyptian monotheism and as a result,although Egypt hosted the chosen, Egyptians did not become chosen.

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

At some point after the fall of the Berlin Wall, when the great cold war opponent that Blish, Clarke, and Pournelle thought would last into future history just sort of curled up and died, I remember reading an article jokingly claiming that all of these good news stories couldn't be business as usual - it had to be alien influence behind the scenes.

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

At some point after the fall of the Berlin Wall, when the great cold waropponent that Blish, Clarke, and Pournelle thought would last into futurehistory just sort of curled up and died, I remember reading an articlejokingly claiming that all of these good news stories couldn't be businessas usual - it had to be alien influence behind the scenes.

Don't forget Laumer's war between "East" and West. No Bolos in our timeline.

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

At some point after the fall of the Berlin Wall, when the great cold waropponent that Blish, Clarke, and Pournelle thought would last into futurehistory just sort of curled up and died, I remember reading an articlejokingly claiming that all of these good news stories couldn't be businessas usual - it had to be alien influence behind the scenes.

Don't forget Laumer's war between "East" and West. No Bolos in our timeline.Is that a good thing or a bad thing?

Too early to say that won't happen.

--Inquiring minds want to know while minds with a self-preservationinstinct are running screaming.

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

At some point after the fall of the Berlin Wall, when the great cold waropponent that Blish, Clarke, and Pournelle thought would last into futurehistory just sort of curled up and died, I remember reading an articlejokingly claiming that all of these good news stories couldn't be businessas usual - it had to be alien influence behind the scenes.

Don't forget Laumer's war between "East" and West. No Bolos in our timeline.Is that a good thing or a bad thing?

Too early to say that won't happen.

Too early to say that something like them might happen, but in theBolo universe the Mark III went into production last year.

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

At some point after the fall of the Berlin Wall, when the great cold waropponent that Blish, Clarke, and Pournelle thought would last into futurehistory just sort of curled up and died, I remember reading an articlejokingly claiming that all of these good news stories couldn't be businessas usual - it had to be alien influence behind the scenes.

Don't forget Laumer's war between "East" and West. No Bolos in our timeline.Is that a good thing or a bad thing?

Too early to say that won't happen.

Too early to say that something like them might happen, but in theBolo universe the Mark III went into production last year.

There is that, but being off by a mere year is nothing in SFnal "prediction" terms. And also, everybody and their grandmother is hand-wringing about AI in military 'bots...

...everybody and their grandmother is hand-wringing about AI in military 'bots...Mark L. Fergerson

Yay, another opportunity to quote long time top robot scientist whose name I keep forgetting. "I can't imagine anyone giving a weapon to something as massively stupid as a robot", and this was the guy who loved robots the most.

...everybody and their grandmother is hand-wringing about AI in military 'bots...Mark L. Fergerson

Yay, another opportunity to quote long time top robot scientist whose name I keep forgetting. "I can't imagine anyone giving a weapon to something as massively stupid as a robot", and this was the guy who loved robots the most.Nils K. Hammer

To predict the rise of killer robots, keep an eye on self-driving cars. In both cases, there is a risk of getting people killed (the wrong people in the case of the killer robots) so standard procedure should be to write a safety case, which conclusively proves that there is no practical risk of killing people. For an AI system with non-trivial vision recognition I think that's decades away, but if the self-driving car people find a way to do this or re-interpret the rules to get away without doing it, the application to killer robots will be obvious. Without such a drastic change, the military will always have to have at least the excuse of claiming there is a soldier in the loop who ordered the killing.

One recent article I read proclaimed the great advantage of an architecture for software on a fighter plane which specifically split the computer system into a safety-critical part and a part that could be written to normal commercial best practice. Finding a way to run stuff on the commercial side not only made it an order of magnitude cheaper to write, it meant that it could be deployed years earlier - so even if you know how to write a killer robot, you could be deploying a system that a soldier-in-the-loop system wipes the floor with, because they can deploy kit that is a generation in advance of the stuff that you have spent a decade proving won't kill the wrong people.

Yay, another opportunity to quote long time top robot scientist whosename I keep forgetting. "I can't imagine anyone giving a weapon tosomething as massively stupid as a robot", and this was the guy wholoved robots the most.

Yay, another opportunity to quote long time top robot scientist whosename I keep forgetting. "I can't imagine anyone giving a weapon tosomething as massively stupid as a robot", and this was the guy wholoved robots the most.

Well, he had something there.Rescue robots, though, may have a future.

Yay, another opportunity to quote long time top robot scientist whosename I keep forgetting. "I can't imagine anyone giving a weapon tosomething as massively stupid as a robot", and this was the guy wholoved robots the most.

Well, he had something there.Rescue robots, though, may have a future.

Should I call Old Glory Insurance?https://www.nbc.com/saturday-night-live/video/old-glory-insurance/n10766:)

Yay, another opportunity to quote long time top robot scientist whosename I keep forgetting. "I can't imagine anyone giving a weapon tosomething as massively stupid as a robot", and this was the guy wholoved robots the most.

Well, he had something there.Rescue robots, though, may have a future.

Yay, another opportunity to quote long time top robot scientist whosename I keep forgetting. "I can't imagine anyone giving a weapon tosomething as massively stupid as a robot", and this was the guy wholoved robots the most.

Well, he had something there.Rescue robots, though, may have a future.

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

At some point after the fall of the Berlin Wall, when the great cold waropponent that Blish, Clarke, and Pournelle thought would last into futurehistory just sort of curled up and died, I remember reading an articlejokingly claiming that all of these good news stories couldn't be businessas usual - it had to be alien influence behind the scenes.

Don't forget Laumer's war between "East" and West. No Bolos in our timeline.Is that a good thing or a bad thing?

Too early to say that won't happen.

Too early to say that something like them might happen, but in theBolo universe the Mark III went into production last year.

There is that, but being off by a mere year is nothing in SFnal "prediction" terms. And also, everybody and their grandmother is hand-wringing about AI in military 'bots...

Post by Thomas KoenigThere are many SF stories about time travellers changingimportant events in the past. So, looking back at ourhistory / timeline, where were they? Are there periodsor events in our history which are unlikely enough sotime travellers at least appear to be plausible?

At some point after the fall of the Berlin Wall, when thegreat cold war opponent that Blish, Clarke, and Pournellethought would last into future history just sort of curledup and died, I remember reading an article jokinglyclaiming that all of these good news stories couldn't bebusiness as usual - it had to be alien influence behindthe scenes.

Don't forget Laumer's war between "East" and West. NoBolos in our timeline.Is that a good thing or a bad thing?

Too early to say that won't happen.

Too early to say that something like them might happen, but inthe Bolo universe the Mark III went into production last year.

There is that, but being off by a mere year is nothing inSFnal "prediction" terms. And also, everybody and theirgrandmother is hand-wringing about AI in military 'bots...

Uh, "the Mark III" implies a Mark II and a Mark I, and neitherof those exist either.

That we know of.--Terry Austin

Proof that Alan Baker is a liar and a fool, and even stupider thanLynn:https://www.cbp.gov/newsroom/stats/sw-border-migration(May 2019 total for people arrested for entering the United Statesillegally is over 132,000 for just the southwest border.)

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

At some point after the fall of the Berlin Wall, when the great cold waropponent that Blish, Clarke, and Pournelle thought would last into futurehistory just sort of curled up and died, I remember reading an articlejokingly claiming that all of these good news stories couldn't be businessas usual - it had to be alien influence behind the scenes.

Don't forget Laumer's war between "East" and West. No Bolos in our timeline.Is that a good thing or a bad thing?

Too early to say that won't happen.

Too early to say that something like them might happen, but in theBolo universe the Mark III went into production last year.

There is that, but being off by a mere year is nothing in SFnal "prediction" terms. And also, everybody and their grandmother is hand-wringing about AI in military 'bots...Mark L. Fergerson

The Bolos did not get true AI until the Mark X.https://en.wikipedia.org/wiki/Bolo_universe#Artificial_intelligence

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

There is an excellent Netflix tv show, Travelers, about why time travelis very problematic.https://www.netflix.com/title/80105699

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

If psychologists ever got hold of time travel and alternate timelines are a thing, they could easily be testing out their theories on timelines that don't lead to their own, running experiments that are now deemed unethical. They could say something like "these people aren't real so any pain they seem to be feeling is an illusion" or similar. It's not as if Idealists have never done anything like that before...

Anyway, imagine two psychs arguing...

"I bet I can get them to go to war over one assassination, say this minor Prince here."

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

If psychologists ever got hold of time travel and alternate timelines are a thing, they could easily be testing out their theories on timelines that don't lead to their own, running experiments that are now deemed unethical. They could say something like "these people aren't real so any pain they seem to be feeling is an illusion" or similar. It's not as if Idealists have never done anything like that before...Anyway, imagine two psychs arguing..."I bet I can get them to go to war over one assassination, say this minor Prince here.""No, you can't- that's silly.""How much cash you got on you?"---"I bet I can get Trump elected President.""That's utterly ridiculous.""How much cash you got on you?"Mark L. Fergerson

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

If psychologists ever got hold of time travel and alternate timelines are a thing, they could easily be testing out their theories on timelines that don't lead to their own, running experiments that are now deemed unethical. They could say something like "these people aren't real so any pain they seem to be feeling is an illusion" or similar. It's not as if Idealists have never done anything like that before...Anyway, imagine two psychs arguing..."I bet I can get them to go to war over one assassination, say this minor Prince here.""No, you can't- that's silly.""How much cash you got on you?"---"I bet I can get Trump elected President.""That's utterly ridiculous.""How much cash you got on you?"Mark L. Fergerson

Good one!

Asimov wrote a shortSPOILER

SPACE

SPOILER

SPACE"Spell My Name With an S" predicated on a minor change having a hugeeffect.

Post by Thomas KoenigThere are many SF stories about time travellers changing importantevents in the past. So, looking back at our history / timeline,where were they? Are there periods or events in our historywhich are unlikely enough so time travellers at least appear tobe plausible?

If psychologists ever got hold of time travel and alternate timelines are a thing, they could easily be testing out their theories on timelines that don't lead to their own, running experiments that are now deemed unethical. They could say something like "these people aren't real so any pain they seem to be feeling is an illusion" or similar. It's not as if Idealists have never done anything like that before...Anyway, imagine two psychs arguing..."I bet I can get them to go to war over one assassination, say this minor Prince here.""No, you can't- that's silly.""How much cash you got on you?"---"I bet I can get Trump elected President.""That's utterly ridiculous.""How much cash you got on you?"Mark L. Fergerson

Asimov's story <https://en.wikipedia.org/wiki/Homo_Sol>comes to mind; are we in it now?

Post by ***@bid.nesAnyway, imagine two psychs arguing..."I bet I can get them to go to war over one assassination, say this minor Prince here.""No, you can't- that's silly.""How much cash you got on you?"---"I bet I can get Trump elected President.""That's utterly ridiculous.""How much cash you got on you?"

Zelazny, _Frost and Fire_, I think.

Dave, I'm also remembering one of a similar concept titled "Blood and Dust",but it doesn't seem to exist

--\/David DeLaney posting thru EarthLink - "It's not the pot that grows the flowerIt's not the clock that slows the hour The definition's plain for anyone to seeLove is all it takes to make a family" - R&P. VISUALIZE HAPPYNET VRbeable<BLINK>my gatekeeper archives are no longer accessible :( / I WUV you in all CAPS! --K.

Post by David DeLaneyDave, I'm also remembering one of a similar concept titled "Blood and Dust",but it doesn't seem to exist

According to the ISFDB, "The Game of Blood and Dust" was published inthe April 1975 issue of _Galaxy_ and collected in _The Last Defenderof Camelot_. Or are you claiming it did exist but was retconned outof the timeline by malicious time travelers?

--David Goldfarb |"...I'm a member of the Centre Extremist party.***@gmail.com | We have very moderate views, but if you don't***@ocf.berkeley.edu | agree with them, we'll kill you."

Post by David DeLaneyDave, I'm also remembering one of a similar concept titled "Blood and Dust",but it doesn't seem to exist

According to the ISFDB, "The Game of Blood and Dust" was published inthe April 1975 issue of _Galaxy_ and collected in _The Last Defenderof Camelot_. Or are you claiming it did exist but was retconned outof the timeline by malicious time travelers?

Jonesing for this story ultimately led me to:https://archive.org/details/Galaxy_v36n04_1975-04/page/n5

This 3 1/2 page short^2 story has two "forward point" inhabitants treatall life on Earth as a disposable plaything.

Along the way to the Zelazny, "The Five Plots of Time" was encountered:

The Five Master Plots of Time Travel Stories

Master plot #1. A man tries to change history and fails.He is doomed to failure, no matter what, because the pastcan’t be changed. ...

Post by D B DavisThe Five Master Plots of Time Travel StoriesMaster plot #1. A man tries to change history and fails.He is doomed to failure, no matter what, because the pastcan’t be changed. ...Master plot #2. A man tries to change the past in somelogically forbidden way. ... The stars go out; the universeends. ...Master plot #3. ... A man tries to fix a tragedy bygoing back in time, but instead makes things worse. ...Master plot #4. A man is in a world different from ours.He tries to change the past, succeeds, and his world morphsinto the “real” world, i. e. ours. ...Master plot #5. A man tries to change history, but insteadcreates a new timeline, or crosses over into an existing alternatetimeline. ...https://sydlogsdon.com/2017/10/30/426-the-five-plots-of-time/If this sort of thing interests you, it's worth a visit to the link.

Ah, I didn't read your post carefully; I Googled, and found thatlink,

https://sydlogsdon.com/2017/10/30/426-the-five-plots-of-time/

after being disappointed I couldn't find that in the issue ofGalaxy.

Of course, in my opinion, while those five basic plotlines dealwith many science-fiction stories about attempts to change knownpast events, in violation of causality...

they omit the _most common_ type of time-travel story.

If you count things like the TV shows "The Time Tunnel", "DoctorWho", and "Quantum Leap", that is.

Someone travels to the past, using an erratic, quirky timetravel device which is not fully controllable. While he isunable to change major events in the past that are known to havehappened, he was _meant_ to arrive at that particular pastmoment in order to...

prevent some major tragedy that *didn't* happen, but would have,if not for him (i.e. flying-saucer aliens landed on Earth in theMiddle Ages, and would have blown it up if not for being foiledby the time traveller), or

alleviate the consequences of a major tragedy by directing anindividual along the right path (i.e. while not being able toprevent the Titanic from sinking, the time traveller encouragesone depressed woman to go forwards to the lifeboats when sheotherwise wouldn't).

So each week they can tell stories about the time travellerdoing some good without ever bumping into a causality paradox.

Post by D B DavisThe Five Master Plots of Time Travel StoriesMaster plot #1. A man tries to change history and fails.He is doomed to failure, no matter what, because the pastcan’t be changed. ...Master plot #2. A man tries to change the past in somelogically forbidden way. ... The stars go out; the universeends. ...Master plot #3. ... A man tries to fix a tragedy bygoing back in time, but instead makes things worse. ...Master plot #4. A man is in a world different from ours.He tries to change the past, succeeds, and his world morphsinto the “real” world, i. e. ours. ...Master plot #5. A man tries to change history, but insteadcreates a new timeline, or crosses over into an existing alternatetimeline. ...https://sydlogsdon.com/2017/10/30/426-the-five-plots-of-time/If this sort of thing interests you, it's worth a visit to the link.

Ah, I didn't read your post carefully; I Googled, and found thatlink,https://sydlogsdon.com/2017/10/30/426-the-five-plots-of-time/after being disappointed I couldn't find that in the issue ofGalaxy.Of course, in my opinion, while those five basic plotlines dealwith many science-fiction stories about attempts to change knownpast events, in violation of causality...they omit the _most common_ type of time-travel story.If you count things like the TV shows "The Time Tunnel", "DoctorWho", and "Quantum Leap", that is.Someone travels to the past, using an erratic, quirky timetravel device which is not fully controllable. While he isunable to change major events in the past that are known to havehappened, he was _meant_ to arrive at that particular pastmoment in order to...prevent some major tragedy that *didn't* happen, but would have,if not for him (i.e. flying-saucer aliens landed on Earth in theMiddle Ages, and would have blown it up if not for being foiledby the time traveller), oralleviate the consequences of a major tragedy by directing anindividual along the right path (i.e. while not being able toprevent the Titanic from sinking, the time traveller encouragesone depressed woman to go forwards to the lifeboats when sheotherwise wouldn't).So each week they can tell stories about the time travellerdoing some good without ever bumping into a causality paradox.John Savard

Post by D B DavisThe Five Master Plots of Time Travel StoriesMaster plot #1. A man tries to change history and fails.He is doomed to failure, no matter what, because the pastcan’t be changed. ...Master plot #2. A man tries to change the past in somelogically forbidden way. ... The stars go out; the universeends. ...Master plot #3. ... A man tries to fix a tragedy bygoing back in time, but instead makes things worse. ...Master plot #4. A man is in a world different from ours.He tries to change the past, succeeds, and his world morphsinto the “real” world, i. e. ours. ...Master plot #5. A man tries to change history, but insteadcreates a new timeline, or crosses over into an existing alternatetimeline. ...https://sydlogsdon.com/2017/10/30/426-the-five-plots-of-time/If this sort of thing interests you, it's worth a visit to the link.

Ah, I didn't read your post carefully; I Googled, and found thatlink,https://sydlogsdon.com/2017/10/30/426-the-five-plots-of-time/after being disappointed I couldn't find that in the issue ofGalaxy.Of course, in my opinion, while those five basic plotlines dealwith many science-fiction stories about attempts to change knownpast events, in violation of causality...they omit the _most common_ type of time-travel story.If you count things like the TV shows "The Time Tunnel", "DoctorWho", and "Quantum Leap", that is.Someone travels to the past, using an erratic, quirky timetravel device which is not fully controllable. While he isunable to change major events in the past that are known to havehappened, he was _meant_ to arrive at that particular pastmoment in order to...prevent some major tragedy that *didn't* happen, but would have,if not for him (i.e. flying-saucer aliens landed on Earth in theMiddle Ages, and would have blown it up if not for being foiledby the time traveller), oralleviate the consequences of a major tragedy by directing anindividual along the right path (i.e. while not being able toprevent the Titanic from sinking, the time traveller encouragesone depressed woman to go forwards to the lifeboats when sheotherwise wouldn't).So each week they can tell stories about the time travellerdoing some good without ever bumping into a causality paradox.John Savard

My present theory about Doctor Who is that every timehe/she (or anyone else, including bad guys) changeshistory with time travel, there are consequences, forsubsequent events at least, and changes everywhere.And job security.

The main evidence is that he/she has witnessed orcaused three different versions of the fall of Atlantis,and utterly destroyed his great enemies the Daleksmore than once. Evidently this got undone and hehad to, um, do it again.

This has been taken to the extreme level of recentlyhaving his 1960s version meet a woman from the distantfuture (2017) and describe a theory of his, if I understoodcorrectly, that logically, in good versus evil,evil should generally win; but, hopping around in time,he has found that not happening. A factor is missingin his calculation. Her idea: "Perhaps there's justsome bloke, wandering around, putting everything rightwhen it goes wrong." Namely, him.

Oh, and he's prevented the destruction of the universemore than once - so if someone undoes /him/ withtime travel then it had better be un-undone fast.

Post by David DeLaneyDave, I'm also remembering one of a similar concept titled "Blood and Dust",but it doesn't seem to exist

According to the ISFDB, "The Game of Blood and Dust" was published inthe April 1975 issue of _Galaxy_ and collected in _The Last Defenderof Camelot_. Or are you claiming it did exist but was retconned outof the timeline by malicious time travelers?

Jonesing for this story ultimately led me to:https://archive.org/details/Galaxy_v36n04_1975-04/page/n5

This 3 1/2 page short^2 story has two "forward point" inhabitants treatall life on Earth as a disposable plaything.

Addendum:

"The Game of Blood and Dust"

Along the way to the Zelazny, "The Five Plots of Time" was encountered:

The Five Master Plots of Time Travel Stories

Master plot #1. A man tries to change history and fails.He is doomed to failure, no matter what, because the pastcan’t be changed. ...

Post by David DeLaneyDave, I'm also remembering one of a similar concept titled "Blood and Dust",but it doesn't seem to exist

According to the ISFDB, "The Game of Blood and Dust" was published inthe April 1975 issue of _Galaxy_ and collected in _The Last Defenderof Camelot_. Or are you claiming it did exist but was retconned outof the timeline by malicious time travelers?

Oh, okay - I have obviously disconfabulated it into memories of two stories,and then smooshed the Frost and Fire title of another Zelazny book onto one ofthem. And Now You Know.

Dave, the time-travelers thing I need for some OTHER stuff, but thanks

--\/David DeLaney posting thru EarthLink - "It's not the pot that grows the flowerIt's not the clock that slows the hour The definition's plain for anyone to seeLove is all it takes to make a family" - R&P. VISUALIZE HAPPYNET VRbeable<BLINK>my gatekeeper archives are no longer accessible :( / I WUV you in all CAPS! --K.

Okay, since folks valued the quote, the guy was Hans Moravec. I think he came up with the idea of "bush robots" which are scalable groups of small bots holding hands and linking computational power in whatever size working group is needed to get a job done.